A Tanzanian businessman and former member of parliament for the ruling CCM party was seized by unidentified men in Dar es Salaam on Thursday, the regional commissioner said.

Mohammed Dewji, the owner and president of the multi-billion dollar revenue Mohammed Enterprises Tanzania Ltd (METL Group), was seized as he arrived for a morning workout at a luxury hotel in the country's commercial capital.

Dar es Salaam regional commissioner Paul Makonda said the businessman was kidnapped by two men as he entered the hotel.

"They fired a gun and then they opened the gate," Makonda said, adding that security personnel had started a search for Dewji.

Witnesses, including the guards manning the gate at the hotel, were being questioned, he said.

Dewji was elected to parliament on the CCM ticket but did not seek re-election to his seat in the 2015 election.

The METL Group has more than 30 factories making consumer products ranging from bicycles and detergents to edible oil and beverages. Other investments cover the agriculture, infrastructure, energy and mobile phone sectors.

The company operates in 11 African nations, mostly in East Africa. Dewji said in 2015 that it had revenues of $2 billion and employed 24,000 people.